Originally Posted by corporate-wage-slave

A colleague has pointed out this very interesting study completed by the Environmental Science and Research (ESR) institute, a Crown Reseach Institute in New Zealand. It's hot off the press, published 19 November, and features in today's Washington Post. The research paper is more interesting than WaPo's version, and relates to a set of passengers who were discovered positive at varying stages after the flight, having in many cases tested negative before departure. The report says it was "likely" they caught Covid-19 on board the 18 hour flight - amazingly some of the passengers did not wear masks, even though the flight was at the end of September. The flight was from Dubai to Auckland, with a refuelling stop in KUL where no-one got on or off. The arriving passengers were quarantined on arrival, found to be positive and the genome testing meant that the cross contamination could be clearly established.

In particular look at the graph on page 6 which encapsulates the report in one diagram. Each colour bar is a passenger, the top one, in deep orange, is passenger F. That passenger was tested on 25 September, before the flight, and found negative. On 2 October the passenger was tested again, after arrival, also negative. But then found to be positive on 8 October. Then look at passenger D (green bar), different story, but pre-tested, and then found to be positive. And to reiterate, these people where in quarantine from soon after arrival, so it's a tight system here.

There is a wealth of other information in this report. But in essence it demonstrates why the UK is right not to rely on a single pre-departure test - it simply doesn't work.